1. Field of the Invention
The present invention relates to an insertion apparatus and an insertion body that can be inserted into a narrow hole, and a rotation unit and a rotative force transmission unit that can be detachably attached to the insertion body.
2 Description of the Related Art
For example, an insertion section of an endoscope disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2007-185394 includes a rotative force transmission unit including a rotation gear and a drive shaft fixed to a proximal end of the rotation gear. When a rotative force is transmitted to the rotation gear via the drive shaft of the rotative force transmission unit, a cylindrical spiral section including inner teeth engaged with the rotation gear rotates according to rotation of the rotation gear.